When you insert or delete cells, rows or columns in a table, the Behaviour of rows/columns options determine how the neighbouring elements are affected. For example, you can only insert new rows and columns into a table with fixed row and column dimensions if space permits.
Note that these properties are valid only for changes to the column width that are made using the keyboard. Using the mouse, you are free to make any column width changes.
To set the Behaviour of rows/columns options for tables in text documents, choose Tools - Options - Office Writer - Table. There are three display modes for tables: